Portable heating unit

ABSTRACT

A portable self-contained temperature controlling unit is removably inserted in a shipping container so that the contents may be heated or cooled during shipment. In the instance of heating, the portable unit derives its heat output from the operation of an internal combustion engine which is embodied in the unit along with its fuel supply. The heating unit includes primary and secondary air circuits in heat exchange relation with each other, and connections of these circuits to outside air have thermostatically controlled valves arranged so that the heat output of the unit is regulated while the operating speed of the engine remains constant.

United States Patent [191 Beaudet Jan. 1, 1974 [5 PORTABLE HEATING UNIT 2,235,967 3/1941 Sunday 123/1425 R i 2,507,1l3 S19 M h 11 .,1 314. R [75] Inventor: Maurice Beaudet, St. Philippe de 50 ms 3 2 l 2 5 LaPrairie, Quebec, Canada Primary ExaminerClarence R. Gordon [73] Assignee: Gait Equipment Ltd., Canduac, Attorney petherstonhaugh & Cm

Quebec, Canada [22] Filed: Mar. 19, 1971 7 ABSTRACT [21] Appl. No.: 126,114 A portable self-contained temperature controlling unit Foreign Application Priority Data Mar. 20, 1970 Great Britain 13,558/

[52] U.S. Cl... 237/123 C, 123/1425, /64 [51] Int. Cl B60h 1/22 [58] Field of Search l23/41.7, 142.5; 237/l2.1, 12.3 A, 12.3 C; 165/64, 52, 51

[56] References Cited UNITED STATES PATENTS 2,286,854 6/1942 Holthouse 237/123 C 3,025,407 3/1962 Robson 237/l2.1 X

is removably inserted in a shipping container so that the contents may be heated or cooled during shipment. In the instance of heating, the portable unit derives its heat output from the operation of an internal combustion engine which is embodied in the unit along with its fuel supply. The heating unit includes primary and secondary air circuits in heat exchange relation with each other, and connections of these circuits to outside air have thermostatically controlled valves arranged so that the heat output of the unit is regulated while the operating speed of the engine remains constant.

5 Claims, 6 Drawing Figures PATENTEU 11374 SHEET 1 0F 5 INVENTOR Maurice BEAUDET PATENT A L" I PAIENTEU 11W 3.782.628

SHEEI 2 0F 5 v INVENTOR Maurice BEAUDET PATENT ,NTS

PATENTEDJAN 11w 3.782.628

. INVENT Maurice BEAUD PORTABLE HEATING UNIT This invention relates to new and useful improvements in shipping containers commonly used for trans port of cargo by truck, rail, plane or ship. Such containers are commonly of a standardized type designed for repeated use in the shipment of various different commodities. Under some circumstances it is desirable for the contents to be heated or to be cooled during shipment, while under other circumstances heating or cooling is not at all needed. To the extent that a controlled temperature is desirable, it is not always expeditious or practical to depend upon facilities of the transporting vehicle to maintain the shipping containers and contents thereof at a desired temperature. Thus, a need has arisen for providing a temperature controlling unit which may be directly associated with a particular container to heat or cool the contents thereof without relying on temperature conditioning facilities which the transporting vehicle may or may not have.

It is the principal object of the invention to fulfill this need by providing a portable, self-contained temperature controlling unit which may be quickly and easily installed in a shipping container when the contents are to be heated or cooled, and which may be readily removed from the container when heating or cooling is not necessary.

Another important object of the invention is to provide aportable temperature conditioning unit which, specifically, is a heating unit readily insertable in and removable from a shipping container, the unit deriving its heat output from the operation of an internal combustion engine which is embodied in the unit along with its fuel supply, so that the unit is completely selfcontained.

In conjunction with the foregoing, another object of the invention is to provide a portable, self-contained heating unit in which the air flow is controlled by thermostatically actuated valves having connections to outside air, so that the heat output of the unit is automatically regulated while the operating speed of the engine remains constant.

With the foregoing more important objects and features in view and such other objects and features which may become apparent as this specification proceeds, theinvention will be understood from the following description taken in conjunction with the accompanying drawings, wherein like characters of reference designate like parts, and wherein: 1

FIG. I is a perspective view, partly broken away, showing a shipping container with the temperature controlling unit of the invention;

FIG. 2 is an enlarged perspective view of the unit per se, the unit specifically being a heating unit;

FIG. 3 is a fragmentary perspective view of the heating unit, taken in the direction of the arrow 3 in FIG.

FIG. 4 is a bottom plan view of the unit;

FIG. 5 is a largely diagramatic longitudinal sectional view of the unit, taken substantially in the plane of the line 5-5 in FIG. 2; and

FIG. 6 is a crosssectional view, taken substantially in the plane of the line 6-6 in FIG. 5 and also showing by dotted lines adjacent portions of the shipping container.

Referring now to the accompanying drawings in detail, in FIG. 1 the general reference numeral 10 designates a conventional standard shipping container which 2 t is provided at one end thereof with loading doors 11, the container walls being provided at the inside thereof with sets of mutually spaced battens 12, 12a, 12b in the conventional manner.

In accordance with the invention, a portable selfcontained temperature controlling unit 13 is removably inserted in the container 10 so that the contents thereof may be heated or cooled during shipment. The unit 13 is removably inserted in a compartment 14, the latter being formed by providing a right-angularly shaped partition plate 15 in the lower end portion of the container remote from the doors 1]. The partition plate I5 includes a vertical wall 15a which extends across the battens 12b on the bottom 16 of the container, and a horizontal wall 15b which extends across the battens 12a on the end wall 17 of the container, as will be clear from FIG. 1 and also from FIG. 6. The partition plate spans the full width of the container between the side walls 18, 19, and due to the spaces between the battens 12a and 12b, the compartment 14 is in air communication with the rest of the container interior. The compartment 14 has an access opening in the container side wall 18, through which opening the temperature conditioning unit 13 may be slidably inserted in or removed from the compartment. The unit is provided at one end thereof with a plate 20 which closes the access opening, in the container side wall 18 when the unit is inserted in the compartment. i

As will be apparent from FIGS. 2 and 4, the temperature conditioning unit 13 includes a housing .21 which is of such size and shape as to occupy the entire compartment 14 when it is slidably inserted thereinto. The housing 21 includes a back wall 2.2 and a bottom wall 23, the back wall being provided with an air inlet slot or opening 24 so that when the unit is inserted in the compartment and thehousing back wall 22 is disposed against the battens 12a on the container end wall 17, air from the interior of the container may flow through the spaces between the battens 12a as indicated at 25 in FIG. 6, and through the inlet opening 24 into the housing 21, as indicated at 26. Similarly, the bottom wall 23 of the housing is provided with an air outlet opening 27, so that air which has been temperatureconditioned within the housing may .be discharged through the opening and through spaces between the battens 12b as at 28 into the interior of the container as at 29. In this manner the air inside the container is circulated through the unit 13 and is heated or cooled thereby so that the contents of the container may be kept at a desired temperature.

The temperature conditioning unit 13 as hereinafter described in detail is a heating unit which is intended to heat the contents of the container during shipment. However, it may be replaced by a cooling unit intended to cool the contents of the container. In actual practice, a heating unit may be installed in the container at the start of its journey and may be with-drawn at some point along the journey and replaced by a cooling unit. Generally speaking, a heating or cooling unit is installed in the container for transportation by road or rail. Where a part of the journey involves transfer of the container to a ship, neither a heating unit nor a cooling unit is necessary inasmuch as the temperature in the hold of j the ship is usually maintained at a uniform level by the outside water. However, if the journey should originate, for example, in a hot climate, a cooling unit could be installed and withdrawn when the container is about to be lowered into the hold of the ship. If the journey is to a cold climate, a heating unit could be installed as soon as the container is lifted out of the hold and would remain until the container reaches its destination. This sequence, of course, would be reversed if the journey were from a cold to a hot climate.

Also generally speaking, heating units would be re- I quired only in cold parts of the world and cooling units in the tropics. Thus, in between the two, either heating or cooling units installed at the start of a journey would not be required at the destination. Accordingly, several units removed from several containers may be packed in one empty container and shipped back to a port where they would be required to be used again. This can be done at very little expense and avoids the storage of a large number of units at one or the other end of a ships voyage, and overhead is thus greatly reduced.

Reference is now drawn to FIG. 5 which shows, somewhat diagramatically, a typical arrangement of the unit 13 as a heating unit. The same is characterized in that the heat output of the unit is derived from the operation of a small internal combustion engine 30 which is air-cooled and is suitably installed in the unit housing 21 along with its fuel tank 31. The engine drives a fan or blower 32, the purpose of which will be hereinafter explained.

A combustion air intake pipe 33 extends from the end of the housing 21 to the engine and an exhaust pipe 34 extends from the engine through the opposite end 35 of the housing. The interior of the housing is suitably partitioned to provide an engine compartment 36 communicating with a heat transfer duct 37 which encloses the exhaust pipe 34 and may also accommodate a muffler 34a on the exhaust pipe. The duct 37 has an extension 38 for returning air to the engine compartment 36. The compartment 36 and the ducts 37, 38 constitute the primary air circuit within the housing 21, in which circuit the air is heated by operation of the engine 30 and is circulated as indicated by the arrows 39. The primary air circuit is continuous, but is provided with a primary air inlet 40 and a primary air outlet 41, both of which communicate with the atmosphere at the outside of the housing end 20. Butterfly valves 42, 43 in the inlet 40 and outlet 41, respectively, are simultaneously opened or closed by automatic controls (not shown) actuated by a thermostat 44 in the primary air circuit. In addition to the aforementioned blower 32, the engine 30 has the usual cooling fan (not shown) which serves to circulate the air past the engine and past the exhaust pipe 34 in the primary air circuit, as shown by the arrows 39.

The partitioning of the interior of the housing 21 is also such as to provide a secondary air circuit obtained by the entry of air from the shipping container into the housing opening 24 as indicated by the arrows 25, 26. The air entering the opening 24 flows across a partition 37' supporting the duct 37 as shown in FIG. 6, the air thus being heated by the duct 37 and entering the secondary heat transfer chamber 45 where it also comes in heat exchange contact with the duct extension 38, before being discharged through the outlet opening 27 as at 28 and 29 into the shipping container to heat the contents of the latter. The chamber 45 contains baffles 45a, 45b around which the secondary air passes as indicated at 46 on its way to the outlet opening 27. The engine driven blower 32 is disposed in the heat transfer chamber 45 to circulate the secondary air through the housing.

The circulation of secondary air through the housing and through the container interior is continuous, but a secondary air inlet 47 and a secondary air outlet 48 communicate the chamber 45 with the outside of the housing at the housing ends 20 and 35, respectively. Butterfly valves 49, 50 in the inlet 47 and outlet 48, respectively, are simultaneously opened or closed by automatic controls (not shown) actuated by a thermostat 51 in the chamber 45.

It should be mentioned at this point that the side wall 19 of the shipping container 10 is provided with an opening at the end of the compartment 14 so that when the unit 13 is installed in the compartment, the end 35 of the unit housing 21 is exposed through the opening in the container wall 19 and the secondary air outlet 48 as well as the exhaust pipe 34 discharge into the atmosphere outside of the shipping container. Conveniently, the exposed end 35 of the unit housing may also be equipped with a filler cap 52 and with a fuel level sight gauge 53 for the fuel tank 31, as shown in FIG. 2.

Similarly, the other end 20 of the unit housing 21, which closes the access opening in the container side wall 18, has the combustion air intake pipe 33, the primary air inlet 40 and outlet 41, and the secondary air inlet 47 in communication with the atmosphere at the outside of the shipping container, as will be apparent from FIG. 3. The housing end plate 20 is equipped with latches 54 to engage suitable catches on the container side wall 18 for retaining the entire unit 13 in position in the compartment 14. Also, the plate 20 may be provided with a door 55 for access to a chamber 56 in the housing 21, which chamber may accommodate controls for the engine 30, and the like.

When the unit 13 is removed from the shipping container, the access openings in the container walls 18 and 19 are closed off by suitable blank plates or covers.

In a typical operation of the heating unit, the secondary air circuit thermostat 51 may be set at F., and the primary air circuit thermostat 44 may be set at F. The thermal capacity of the heating unit is controlled by the speed of the engine 30 which is set at a given speed and that setting normally is not changed while the unit is in operation. The substantially constant engine speed therefore makes the heating unit completely autonomous as the heat output adjusts itself to the temperature outside the shipping container while retaining the temperature within the container at the demand of variations of temperature from outside to inside of the container. This, of course, is effected by opening or closing of the valves 42, 43 and of the valves 49, 50 which communicate the respective primary air and secondary air circuits with the outside atmosphere under varying temperatures as sensed by the thermostats 44 and 51.

When contents of the shipping container are such that heating of the container is required, the heating unit 13 is simply slid into the compartment 14 and fastened in position by the latches 54. The engine 30 is started by means of controls in chamber 56 and the air circulated through the unit plus the volume of primary and/or secondary air to be admitted or bled off is automatically controlled by the thermostats to maintain the desired temperature within the container.

While in the foregoing there has been described and shown the preferred embodiment of the invention, various modifications and equivalents may be resorted to within the spirit and scope of the invention as claimed.

What is claimed as new is:

1. A portable self-contained heating unit comprising a housing, an internal combustion engine provided in said housing, a supply of fuel in the housing for said engine, said engine having a combustion air intake and an exhaust pipe communicating with the exterior of the housing, a continuous primary air circuit provided in the housing past said engine and said exhaust pipe, a secondary air circuit through the housing in heat exchange relation with said primary air circuit, and a blower driven by said engine for circulation of air through the secondary air circuit.

2. The device as defined in claim 1 together with thermostatically.controlled air inlet and outlet valve means communicating each of said primary and secondary air circuits with the exterior of said housing.

3. The device as defined in claim 1 together with a valved primary air inlet and a valved primary air outlet communicating said primary air circuit with the exterior of said housing, and a thermostat within the primary air circuit for controlling the valved air inlet and outlet.

4. The device as defined in claim 1 together with a valved secondary air inlet and a valved secondary air outlet communicating said secondary air circuit with the exterior of said housing, and! a thermostat within the secondary air circuit for controlling the valved air inlet and outlet.

5. The device as defined in claim 1 together with a valved primary air inlet and outlet and a valved secondary air inlet and outlet communicating the respective primary and secondary air circuits with the exterior of said housing, and thermostats within the respective primary and secondary air circuits for controlling the primary air inlet and outlet and secondary air inlet and outlet respectively, the device being further characterized in that the heat output of the heating unit is controlled by the valued air inlets and outlets while the operating speed of said engine remains substantially constant. 

1. A portable self-contained heating unit comprising a housing, an internal combustion engine provided in said housing, a supply of fuel in the housing for said engine, said engine having a combustion air intake and an exhaust pipe communicating with the exterior of the housing, a continuous primary air circuit provided in the housing past said engine and said exhaust pipe, a secondary air circuit through the housing in heat exchange relation with said primary air circuit, and a blower driven by said engine for circulation of air through the secondary air circuit.
 2. The device as defined in claim 1 together with thermostatically controlled air inlet and outlet valve means communicating each of said primary and secondary air circuits with the exterior of said housing.
 3. The device as defined in claim 1 together with a valved primary air inlet and a valved primary air outlet communicating said primary air circuit with the exterior of said housing, and a thermostat within the primary air circuit for controlling the valved air inlet and outlet.
 4. The device as defined in claim 1 together with a valved secondary air inlet and a valved secondary air outlet communicating said secondary air circuit with the exterior of said housing, and a thermostat within the secondary air circuit for controlling the valved air inlet and outlet.
 5. The device as defined in claim 1 together with a valved primary air inlet and outlet and a valved secondary air inlet and outlet communicating the respective primary and secondary air circuits with the exterior of said housing, and thermostats within the respective primary and secondary air circuits for controlling the primary air inlet and outlet and secondary air inlet and outlet respectively, the device being further characterized in that the heat output of the heating unit is controlled by the valued air inlets and outlets while the operating speed of said engine remains substantially constant. 